The Suez crisis and the choice of Eden's successor led, in 1957, to the first major personal criticism of the Queen. In a magazine, which he owned and edited, Lord Altrincham accused her of being "out of touch". Altrincham was denounced by public figures and slapped by a member of the public appalled by his comments. Six years later, in 1963, Macmillan resigned and advised the Queen to appoint the Earl of Home as prime minister, advice she followed. The Queen again came under criticism for appointing the prime minister on the advice of a small number of ministers or a single minister. In 1965 the Conservatives adopted a formal mechanism for electing a leader, thus relieving her of involvement.
In 1957 she made a state visit to the United States, where she addressed the United Nations General Assembly on behalf of the Commonwealth. On the same tour, she opened the 23rd Canadian Parliament, becoming the first monarch of Canada to open a parliamentary session. Two years later, solely in her capacity as Queen of Canada, she revisited the United States and toured Canada. In 1961 she toured Cyprus, India, Pakistan, Nepal, and Iran. On a visit to Ghana the same year, she dismissed fears for her safety, even though her host, President Kwame Nkrumah, who had replaced her as head of state, was a target for assassins. Harold Macmillan wrote, "The Queen has been absolutely determined all through ... She is impatient of the attitude towards her to treat her as ... a film star ... She has indeed 'the heart and stomach of a man' ... She loves her duty and means to be a Queen." Before her tour through parts of Quebec in 1964, the press reported extremists within the Quebec separatist movement were plotting Elizabeth's assassination. No attempt was made, but a riot did break out while she was in Montreal; the Queen's "calmness and courage in the face of the violence" was noted.
In the 1950s, as a young woman at the start of her reign, Elizabeth was depicted as a glamorous "fairytale Queen". After the trauma of the Second World War, it was a time of hope, a period of progress and achievement heralding a "new Elizabethan age". Lord Altrincham's accusation in 1957 that her speeches sounded like those of a "priggish schoolgirl" was an extremely rare criticism. In the late 1960s, attempts to portray a more modern image of the monarchy were made in the television documentary Royal Family and by televising Prince Charles's investiture as Prince of Wales. In public, she took to wearing mostly solid-colour overcoats and decorative hats, which allow her to be seen easily in a crowd.